Sunder
by Lif61
Summary: After Sam gets mugged Dean sees it as his responsibility to get revenge. (Takes place during season 10.)


Usually Sam could hold his own in a fight, but that was when he was sober. At the current moment he certainly wasn't that. He didn't drink in copious amounts like Dean tended to, but after a really rough day sometimes he just needed something to help him escape the horrors of his life. As he lay on the ground, trying to work through the pain in his body, rain pattering against him, Sam really regretted having a few too many drinks.

It was late when he'd left the bar, and a group of men had jumped him with the intention of stealing his wallet. He didn't really care about the money, but he hadn't wanted to just hand it over to them. That wasn't who he was. So Sam had tried to fight, and in his drunken state he'd failed miserably. He knew he had to pick himself up off the ground and somehow get back to the motel he and Dean were staying at, but he was tired and dizzy.

With a groan of pain he pushed himself up into a sitting position. A wince left him from the way the movement pulled at the shallow knife wound in his side. Pressing one hand firmly against it so he wouldn't lose too much blood, Sam used his other hand to try and grab his phone.

After retrieving it from his pocket he tried dialing Dean, but he fumbled a lot and the phone fell from his hand. Sam felt around for it for a bit. It was dark in the narrow street he was in. His phone provided light, but in his current state he couldn't quite pinpoint where it was.

He finally managed to get a hold of it, and this time he was able to call Dean without much issue.

His brother picked up almost immediately. Sam didn't tell him what had happened; just that he needed a ride because he'd had too much to drink.

After assuring that he'd be there soon, Dean hung up, and Sam was left to wait for his brother, growing colder as the rain soaked into his clothes.

Sam must've dozed off because the next thing he was aware of was Dean rushing over to him. His older brother gently grasped his shoulders as he observed him.

"What happened to you?" he asked.

"Later," Sam said, hoping Dean would understand what he meant by that; using too many words seemed difficult at the moment. "Jush ge'me to the car."

"Okay, yeah, you're drunk all right," Dean surmised as he helped Sam to his feet. Standing made his head spin and he leaned heavily on Dean, causing him to stumble. "Hey, you gotta help me out here. I can't carry you like you're a baby."

"O-okay."

Sam did his best to straighten himself so he wasn't leaning on his brother so much. Once they were settled in the car Sam rested his head against the window. In his current state the cold glass felt soothing.

Dean didn't say anything on the way back to the motel. Thankfully it wasn't too long of a ride, and once they got inside Dean helped Sam out of his jacket.

"Please tell me you can change into something dry on your own," Dean said, a mild look of disgust on his face at the thought of having to help his brother with that particular task.

"I can do it," Sam assured him.

At the moment that was easier said than done, but eventually Sam stumbled from the bathroom, wearing sweatpants and a white t-shirt. Without another word he flopped down onto his bed and promptly passed out.

* * *

A burning sensation in his side woke Sam and he blearily opened his eyes. He was met with the sight of his shirt lifted up, exposing the slash on the lower right part of his abdomen, and Dean was tending to it. For some reason the wound was bleeding again, and from what Sam could tell it'd already been stitched up.

There was a stinging sensation, and then something was traveling through his skin, pulling at it slightly.

"This is a fun way to wake up," Sam said sarcastically, rubbing at his forehead as an ache began to take hold.

"Yeah, sorry, man. I stitched you up last night after you passed out. I don't know how, but you pulled some of them out in your sleep. I blame the cheap ass dental floss."

Dean ran the needle through him again and Sam flinched away.

"Stay still," his brother reprimanded him. "You're gonna screw me up."

"It hurts," Sam complained.

"Yeah, I know. Now quit being a wuss."

Sam let Dean finish without further complaint. After his brother got him a glass of water he sat down on his own bed across from him. With his sleeves rolled up, the Mark of Cain was visible, and Sam eyed it wearily.

"So who did this to you?" Dean asked.

With those few words his entire demeanor changed. He was no longer gentle (well, what passed as gentle for him) and patient like he had been while helping Sam. Now, he was ready to find out who had hurt his brother so he could teach them a lesson. With the Mark of Cain on his arm, Sam knew that wasn't a good idea. Dean would take things too far.

Sam shrugged. "Just some guys," he told him. "I was leaving the bar, they wanted my wallet, I tried to fight them, and then…" He shrugged again. "You can figure out the rest."

Dean stood and started making his way over to the chair he'd draped his jacket on. Sam rushed to his feet and grabbed a hold of his wrist to stop him, ignoring the way his head and multiple injuries throbbed in indignation.

His brother turned his head and looked at him, some darkness receding from his green eyes.

"What are you planning on doing?" Sam asked.

"I'm planning on finding the bastards who did this to you," Dean started, angrily gesturing at Sam to indicate his injuries, "and I'm gonna make sure they never lay a finger on you again."

"Just let it go, okay? I don't know who attacked me."

"Well I can find out. Now would you let go of me?" Dean pulled his wrist out of Sam's grasp, a glare on his face.

"What are you going to do when you do find them?" Sam asked as his brother made his way over to the chair and put his jacket on. "Just throw a few punches and be on your merry way?"

"Something like that," Dean answered vaguely.

"Hey, look at me. I'm not letting you walk through that door."

"I won't be long."

"That's not the problem, Dean!" Sam shouted, his fear over what his brother might do getting the better of him. He turned away and ran a hand through his hair.

Dean came up to him. "Okay, Sam, then tell me, what's the problem? The way I see it there's nothin' wrong with getting a little revenge."

He turned to him. "It's that _thing_ on your arm! It's changing you, man. I mean, I know revenge is kind of your style, but I'm afraid you'll go too far."

"Too far?" Dean asked incredulously. "What, like murder?"

"Yes, like murder."

Dean scoffed. "This is ridiculous. I'm not gonna murder anyone."

"You say that now, but I've seen what the Mark of Cain does to you when you're in a fight. You'll start, and then you won't be able to stop."

Sam swallowed roughly when he finished speaking, the reality of the situation catching up to him. If Dean walked out that door, if he found the men who had hurt him, there was no doubt in Sam's mind that there would be a few less people walking the Earth by the time the day was done.

Dean was nodding his head slowly as he took in his words. "You know what, maybe you're right." A sigh left him, one that spoke of exhaustion that seeped down into his bones, and then he sat down. "I don't like what the Mark of Cain is turning me into," Dean admitted. "I mean, it's only a matter of time before I become a demon again. Seriously, all someone has to do is kill me and then I'll be running around with black eyes.

A small shiver passed through Sam as he took a seat at the rickety table, across from Dean. Though it'd been months ago, memories of those heart wrenching and frightening moments in the bunker when his brother had been after him with a hammer still plagued his mind and often made their way into his dreams.

"We can figure something out," Sam said quietly.

At times like this, when he was truly faced with who Dean was becoming, he didn't believe they'd figure something out. But the thought of losing his brother, of him becoming a demon again, a monster, it was excruciating. He couldn't let that come to pass. There was no way he'd be able to endure it.

"You know, you're always saying that. It's getting annoying."

Sam lifted up his head, trying to give Dean a reassuring look. It was difficult with the angry and pained gaze his brother was giving him.

"I say that because we can't just give up," Sam explained to him. "That's not what we do. No matter what, we always fight, even if all the odds are stacked against us."

"Sammy," Dean began, straightening in his chair like he was about to explain a very important thing to him, "there are just some battles that we _can't win_. That's just how it goes. Eventually everyone has to face that. I think it's about time that we do."

Sam scrunched up his face in confusion. "Where is this coming from?"

"I don't know," Dean grumbled, putting his face in his hands. "I'm tired, and I _really_ want to go after the sons of bitches that hurt you."

"Dean, you're better than that."

In an instant his brother lifted up his head, his eyes showing emotions so tangled that Sam couldn't make sense of them. "Am I?" he asked. "The way I see it I'm not. I've gone off the reservation countless times, you've even pointed out that I enjoy hunting too much. Hell, I even felt good when I killed all those men who were going to hurt Claire."

"That's all the Mark."

"Is it? What if it's not the Mark, Sam?" Dean paused, and in that moment he looked like a little kid who was learning that the world was much darker than he'd imagined. When he spoke next his voice was quiet, and his voice cracked, "What if it's just _me_?"

"Dean, this violent person you've become, that's not you. I know you, man. You kill for the job, but that doesn't make you who you are. You're the kind of person who saves people, Dean, the kind of person that cares. This _thing_ you're becoming, that's not you."

Dean shook his head and looked away, wiping at his face. Sam suspected that a few tears had begun making their way down his cheeks.

"I don't know that," he admitted. His bottom lip trembled and he went on, "Every day I feel this _burning_ inside of me, wanting to be let out. I hold it in because I'm always thinking, 'I can't do this to Sammy. I can't let him watch me become some monster.' But it gets harder every single day, and sometimes you look at me differently, and I _know_. Maybe you're right, maybe that's not who I am, but I can't shake this feeling that there's always been something inside of me that's not right, broken."

"I admit, we've been through hell and back-"

"Literally," Dean cut in with feigned amusement.

"-but that doesn't mean you're broken. You're still going, we both are, and as long as that's true there's still hope."

Slowly, Dean put his right arm out and rolled his sleeve up, revealing the red, evil mark tainting his skin.

"As long as this remains where it is," Dean stated, his tone resolute, "there is no hope."

Without another word, and before Sam could do anything to stop him, Dean got up from the table and left.

The slam of the door galvanized Sam into action, and he sprung to his feet, racing outside. The sky was a dismal gray, promising more rain to come. Dean was climbing into the Impala, not bothering to look at him.

"Dean, don't do this," Sam pleaded. His brother ignored him, shutting the car door. "Dean!"

Not really having any sort of plan in mind Sam rushed over to the Impala, but Dean was already starting up the engine. Sam watched as his brother drove away, and he was left there in the empty parking lot, his feet bare, and a stain of blood on his white shirt.

* * *

Finding the men who had hurt Sam hadn't been too hard. A flash of a fake badge and he was allowed to look at the security tapes from the night before. Anger simmered in him as he watched the men, five of them, hurt his brother. What was worse was seeing Sam trying and failing to execute moves that he usually excelled at. Maybe if his brother had been a little less drunk he would've been able to protect himself. But that hadn't been the case, so Dean had work to do.

Upon realizing why Dean was looking at the tape the bartender helpfully provided the names of the men and the addresses they could be found at. But that didn't satisfy Dean. He craved a fight like an addict craved their next hit, and one-on-one would be child's play. So he'd wait till he had them all together, and then he'd strike.

After talking to the bartender for a bit Dean learned that the five men were regulars and would most likely be back that night.

Waiting for night time would be excruciating, and he'd have to stay away from the motel or else Sam would try to talk him out of this, but Dean could do it, if only for the sake of being able to lash out, to hurt someone.

Intent on his hunt – as he now liked to think of it – Dean forgot to thank the bartender for the information before he left.

* * *

The day passed in an agonizingly slow manner for both Winchesters. Sam interspersed the dreary hours with time spent lying in bed, trying to forget the pain his injuries were causing him, and calling Dean only to be met with his voicemail. He was getting sick of the words, "Leave your name, number, and nightmare at the tone."

Dean liked to think he had a more productive day than Sam. He spent his time getting a look at each of the men who had hurt his little brother, wanting to make sure he had the right targets. A white-hot rage filled him at the sight of them and it was difficult to stay in the Impala. The Mark of Cain seemed to be burning on his arm, the sensation just as painful as it was sinfully sweet.

It wasn't long after nightfall that the five men went back to the bar, and Dean was ready. He waited outside for them, staying well away from everyone else for fear that he might take his bloodlust out on them. He had a simple knife strapped to his thigh, and in the shadows he stood in no one would be able to tell that he was armed. Though the knife would do just fine he yearned for the First Blade, yearned for the way it seemed to pump adrenaline and sheer power into his veins.

Thankfully the rain had let up for now, but there were still large puddles on the ground. Dean took note of them, knowing that in a fight the water could mess up his footing.

Now that it was almost time to get revenge for them hurting Sam time seemed to pass even more slowly than it had the entire day. It was irritating.

Finally, _finally_ , the men left the bar, stumbling a bit drunkenly. Still, there were five of them and only one of him, so it wasn't like he'd be taking advantage of their drunken state.

Dean stepped up to them. "Evening, fellas," he greeted. His hand itched to just unsheathe the knife and start the fight already, but he wanted them to know why he was doing this to them.

They weren't big, about his size (then again, to other people that was big), and they looked like the kind of men who would hurt someone just for the fun of it. Dean hated people like that.

One of the more inebriated ones peered at him, his eyes unfocused like he was seeing double.

"Can we help you?" another asked.

"I just thought we'd have a talk," Dean began. "You see, last night you mugged a man, and you beat him when he tried to put up a fight."

"Yeah," one of them affirmed, suspicion in his voice. "What's it to ya?"

"That man was my brother."

All five of them broke out in a fit of laughter, and then there were slurred, unintelligible comments. By the tone of their voices they were most likely deprecating. Dean didn't care. With the men having low expectations of him this was going to be very fun. He couldn't wait to surprise them.

One comment he could make out. It came from the one who had first addressed him. "Looks like we've got a hero on our hands, boys."

Always being one for dramatics, Dean took this opportunity. He drew closer to them, unsheathing his knife, and made sure they could all see it.

"Oh, I'm no hero."

His confidence made the men take a step back, their eyes widening as they realized they might have made a mistake.

"W-we're sorry," one of them blubbered. "We'll give yer brother backis money."

"Yeah, here," the more sober one said, taking out a wallet and tossing it to Dean.

Dean deftly caught it, looked to make sure it was Sam's, and then put it in his pocket.

"There, the score's settled."

"The way I see it, it's not," Dean told them. "You hurt him. I don't take anyone hurting my brother lightly."

"Look, man, we're sorry. I-it won't happen again."

Dean smiled, and it didn't reach his eyes. "You're right. It won't."

He lunged towards them, brandishing the knife. With the first stroke of the blade against flesh Dean's mind numbed and he became blissfully lost in the violence. There was just adrenaline, and his rage, and the pain he inflicted. It wasn't a completely outmatched fight, and he struggled, but it made the experience all the more fulfilling. Water splashed all around them as the puddles were upset with the moving feet.

There was blood, the snaps of bones, the cries of pain, and one by one his adversaries lessened until Dean was the only one left standing.

He stood there with his eyes closed, breathing in the cool night air, loving the way his heart beat wildly and the way the Mark of Cain burned blissfully like alcohol. He felt so alive, his senses at their peak, euphoria dancing in his brain. It was all so wonderful.

Long minutes passed before he opened his eyes, and in that time rain had started to fall again, washing away the blood on his skin. He looked at the bodies that lay around him on the wet pavement. It crossed his mind that they were probably dead, but at the moment he didn't particularly care. He just wanted more; more of the vicious dance of bodies, more of the heart-pounding action. It was like every cell in his body craved it, every part of his being.

But he had to accept that the fighting was over. He'd won, and he'd gotten his revenge. But he still didn't feel fulfilled.

Suddenly, something caught Dean's eye, a square of brown leather. He picked it up and examined it. It was Sam's wallet.

 _Huh, must've fallen out of my pocket during the fight._

Looking at it helped bring him back to reality, and he stared at the bodies on the ground. They weren't just bodies, they were men he'd killed.

 _This, this isn't what I do,_ he thought in a panic. _I hunt monsters. I don't_ murder _._

But clearly he now did.

He had to get away. He had to escape the evidence of what he'd done. The euphoria from the Mark still clouded his brain as he left in a hurry.

When Dean got back to the motel Sam was there, pacing.

"Thank god you're okay," his brother said upon seeing him. But Dean didn't respond, just numbly put Sam's wallet on the table. "Dean?"

"I killed them, Sam."

His brother swallowed roughly, and it didn't go without notice that he took half a step back.

Sam turned away from him and said quietly, his voice pained, "We should go."

"Yeah, probably."

They packed up and got ready to leave in tense silence. Dean had had to change due to the blood on his clothes. Thankfully he was an expert on getting out blood stains.

It wasn't till they were on the road that Sam finally said something, "Are we going to just ignore this? You _murdered_ five people, Dean."

"I know."

It hurt to think about what he'd done, about the monster he was becoming. Sam had been right. He shouldn't have walked out that door that morning. He wished he could take it all back.

"And, that's it? Nothing else to say?" Sam prompted.

"What do you want me to say?!" Dean shouted. His anger and bliss still wasn't under control, so part of him was searching for a fight. "That I realize I made a mistake? Yeah, I know that. But that doesn't change the fact that it happened, or the fact that I… _enjoyed_ it."

Out of the corner of his eye he saw Sam open his mouth to say something and then close it again.

"I enjoyed it, Sam," he admitted again. "That's the truth. When I was killing, and there was nothing but the fight, it felt _good_. And it didn't just feel right, it felt like… well, it felt like I was high. Hell, I still feel that way."

"You've never talked about how it felt before," Sam pointed out.

The road wasn't very busy given how late it was, so Dean spared him a glance.

"That's because I knew you'd do this."

"Do what?"

"Look at me different."

Sam pulled his head back as he told him, "I'm not looking at you differently."

"Yes, you are," Dean insisted. His brother looked away, thinking about what he'd said. "Sam, you just gotta accept that this is who I am now."

His brother clenched his jaw and his shook his head. "No. No, I'm not gonna do that. I'm not gonna give up on you, Dean."

"Well you should because what I did tonight, I know I'm gonna do it again. It's only a matter of time."

"I don't believe that."

Suddenly, Dean pulled the car over to the side of the road and put it in park.

He turned to his brother, angrily pointing a finger at him. "You know what, Sam, I am sick of your crap."

"Crap? What crap?"

"This!" Dean yelled, gesturing to him. "This belief that you're going to save me, that you have to save me. Sometimes Sam, you just gotta let things go."

"You're one to talk," Sam spat back.

"What's that supposed to mean?"

Sam wiped a hand over his mouth and then turned to him. "You know damn well what it means! You _never_ let things go, or let things work as they're supposed to. You always have to interfere and screw everything up, screw my life up."

"Sam, what are you talking about?"

"I'm talking about the whole mess with Gadreel, Dean!" his brother shouted at him.

"I thought we were past that!"

At that Sam got out of the car, slamming the door shut. Dean followed him. Neither of them cared that the rain was now falling fiercely.

Sam was pacing. "I can't believe you right now," he told him. "You seriously think I'm past that?! Sure, I forgave you because that's the kind of person I am. But getting over that? That's not gonna happen, Dean. That's not just something I can forget! It was _worse_ than being possessed by a demon. I have all these memories of all the terrible things Gadreel did, and I still count every death as my fault, even Kevin's."

"This is ridiculous! That wasn't your fault! Now get your ass back in the car!"

Sam shook his head. "It still feels like my fault. Angels have that stupid thing with consent, remember? And you know why I was drinking last night, Dean? I was drinking because those memories were kicking me in the ass and making it difficult for me to even do my friggin' job. So yeah, I still suffer from what you did to me, so you don't get the right to tell me to let things go, to not try and find some way to save you."

As Sam had spoken rage was boiling up in Dean again. He knew it was fueled by the Mark of Cain, but at the moment that didn't matter. He was too buried in his emotions to think properly. So he went over to Sam, grabbed the front of his shirt with one hand and then punched him with the other.

And in that moment Sam's emotions got the best of him as well. When Dean released him he barely reeled back from the blow. Rather, he clenched his jaw resolutely and threw a punch of his own. It hit Dean on his cheekbone, and he stumbled back. But he regained his footing and leapt, throwing his arms around Sam's neck so that he had him in a headlock.

His brother used his superior mass to flip him. Dean landed in the mud on his back, the air knocked out of him. But he quickly scrambled to his feet.

An enraged shout left him and he charged at Sam again. He tried to grab onto him, but Dean's momentum was too great and they both fell to the ground. Now it was ugly and brutal, both of them rolling around in the mud, trying and succeeding at hurting the other one.

Thanks to Sam's previous injuries Dean was able to get the upper hand. And now, he straddled his brother, his hands around his throat. With Sam's face exposed to the rain the mud was washing away from his skin allowing Dean to see the fresh blood seeping from multiple wounds.

His heart seemed to stop, and he fell back, off of Sam.

"I'm sorry. Oh god, Sam, I'm so sorry!" Tears were running down his face, and both brothers stayed there, trying to come to grips with what had just happened.

Sam started to rise, and Dean rushed over to help him. His little brother was wary of him at first, but when a groan of pain left him he decided to accept his help.

Dean supported him, much as he had last night, but now the injuries his brother had were his own fault.

As he got Sam into the car he knew his brother would soon forgive him. But Dean knew he wouldn't be able to forgive himself. He drove on, and the rain fell.


End file.
